Effect of maturity and processing on total, insoluble and soluble dietary fiber contents of Indian green leafy vegetables

Nutritional composition of quinoa leafy greens: An underutilized plant-based food with the potential of contributing to current dietary trends

Quinoa (Chenopodium quinoa Willd.) leafy greens (QLGs) are plant-based foods of high nutritional value that have been scarcely studied. In this work, the nutritional and functional composition of three QLGs varieties was evaluated. A protein content higher than 35 g 100 g-1 dw with a well-balanced essential amino acid composition was found making them a good source of vegetable protein. In addition, elevated contents of dietary fibre and minerals, higher than those detected in quinoa seeds and other leafy vegetables, were found. The lipid profile showed higher contents of linoleic (C18:2, ω6) (20.2 %) and linolenic acids (C18:3, ω3) (52.8 %) with low ω6/ ω3 ratios (∼0.4/1). A total sugar content <1 g 100 g-1 dw was found for all varieties tested, lower than that obtained in seeds. The saponin content varied between 0.76 and 0.87 %. Also, high values of total phenolic compounds (969.8-1195.4 mg gallic acid 100 g-1), mainly hydroxycinnamic acids and flavonoids, and great antioxidant activities (7.64-8.90 g Trolox kg-1) were found. Multivariate analysis here used allowed us to classify the samples according to the quinoa variety evaluated, and the sequential stepwise multiple regression applied revealed that the PUFA and sucrose contents negatively influenced the protein content while the palmitic acid content affected positively this parameter. Overall, this study shows that QLGs are promising nutritious and functional plant-based foods supporting the necessity of promoting their cultivation, commercialization, and consumption.

Spinach Methanolic Extract Attenuates the Retinal Degeneration in Diabetic Rats

It has been suggested that spinach methanolic extract (SME) inhibits the formation of advanced glycation end products (AGEs), which are increased during diabetes progression, so it is important to know if SME has beneficial effects in the diabetic retina. In this study, in vitro assays showed that SME inhibits glycation, carbonyl groups formation, and reduced-thiol groups depletion in bovine serum albumin incubated either reducing sugars or methylglyoxal. The SME effect in retinas of streptozotocin-induced diabetic rats (STZ) was also studied (n = 10) in the normoglycemic group, STZ, STZ rats treated with SME, and STZ rats treated with aminoguanidine (anti-AGEs reference group) during 12 weeks. The retina was sectioned and immunostained for Nε-carboxymethyl lysine (CML), receptor RAGE, NADPH-Nox4, inducible nitric oxide synthase (iNOS), 3-nitrotyrosine (NT), nuclear NF-κB, vascular endothelial growth factor (VEGF), glial fibrillary acidic protein (GFAP), S100B protein, and TUNEL assay. Lipid peroxidation was determined in the whole retina by malondialdehyde (MDA) levels. The results showed that in the diabetic retina, SME reduced the CML-RAGE co-localization, oxidative stress (NOX4, iNOS, NT, MDA), inflammation (NF-κB, VEGF, S100B, GFAP), and apoptosis (p < 0.05). Therefore, SME could attenuate the retinal degeneration by inhibition of CML-RAGE interaction.

Optimum Additive Composition to Minimize Fat in Functional Goat Meat Nuggets: A Healthy Red Meat Functional Food

Optimally designed functional foods are considered the most important part of a balanced and healthy diet. Goat meat nuggets, an otherwise healthy option, are packed with undesirable saturated and unsaturated fats. The present work suggests an optimal functional formulation to reduce the surplus fat content of goat meat nuggets by adding two optimally calculated functional ingredients, namely, fenugreek leaves (FL) and psyllium husk (PH). Response surface optimization was performed to determine the optimal content of the functional ingredients (FL and PH), resulting in minimum fat content without affecting the overall acceptability (OA) and other properties representing the taste and texture (e.g., ash content, pH, crude fiber content, and moisture content) of the nuggets. Functional additives at optimum levels successfully reduced the fat content of the weight-conserved nuggets by almost 39% compared with the control nuggets. Minimal and acceptable effects were observed regarding OA and other properties representative of the taste and texture of the nuggets. An optimally designed, fat-attenuated goat meat nugget formulation is therefore prescribed, which complies with the nutritional standards of a balanced diet.

Barriers impairing mineral bioaccessibility and bioavailability in plant-based foods and the perspectives for food processing

Plant-based foods gain more importance since they play a key role in sustainable, low-meat and healthy diets. In developing countries, these food products, especially legumes and cereals, are important staple foods. Nevertheless, the question arises on how efficient they are to deliver minerals and if it is useful to encourage their consumption to reduce the prevalence of mineral deficiencies? This review paper focuses on the discrepancy between the mineral content and the amount of minerals that can be released and absorbed from plant-based foods during human digestion which can be attributed to several inherent factors such as the presence of mineral antinutrients (phytic acid, polyphenols and dietary fiber) and physical barriers (surrounding macronutrients and cell wall). Further, this review paper summarizes the effects of different processing techniques (milling, soaking, dehulling, fermentation, germination and thermal processing) on mineral bioaccessibility and bioavailability of plant-based foods. The positive impact of these techniques mostly relies on the fact that antinutrients levels are reduced due to removal of fractions rich in antinutrients and/or due to their leaching into the processing liquid. Although processing can have a positive effect, it also can induce leaching out of minerals and a reduced mineral bioaccessibility and bioavailability.

Nutritional Components of Amaranth Seeds and Vegetables: A Review on Composition, Properties, and Uses

 A few decades ago Amaranthus was rediscovered as a most promising plant genus that may provide high-quality protein, unsaturated oil, and various other valuable constituents. Since then research has focused on various Amaranthus spp. and has been rapidly expanding, and a large number of reports have been published. Several review articles focusing on different aspects, such as botanical, agrotechnological, compositional, biological, chemical, and technological properties, as well as applications and health effects, have also been published since then. This comprehensive review is focused on amaranth composition, antioxidant properties, applications, and processing. The composition includes macrocomponets (lipids, proteins, carbohydrates, and dietary fiber) and other important constituents, such as squalene, tocopherols, phenolic compounds, phytates, and vitamins. These aspects of amaranth studies have not been comprehensively reviewed for a long time.

Retention of nutrients in green leafy vegetables on dehydration

The objective of the study was to investigate the influence of dehydration on nutrient composition of Amaranthus gangeticus, Chenopodium album, Centella asiatica, Amaranthus tricolor and Trigonella foenum graecum. The green leafy vegetables (GLV) were steam blanched for 5 min after pretreatment and dried in an oven at 60 °C for 10-12 h. The fresh and dehydrated samples were analyzed for selected proximate constituents, vitamins, minerals, antinutrients and dialyzable minerals. Dehydration seems to have little effect on the proximate, mineral and antinutrient content of the GLV. Among the vitamins, retention of ascorbic acid was 1-14%, thiamine 22-71%, total carotene 49-73% and β-carotene 20-69% respectively, of their initial content. Dialyzable iron and calcium in the fresh vegetables ranged between 0.21-3.5 mg and 15.36-81.33 mg/100 g respectively, which reduced to 0.05-0.53 mg and 6.94-58.15 mg/100 g on dehydration. Dehydration seems to be the simplest convenient technology for preserving these sources of micronutrients, especially when they are abundantly available. Irrespective of the losses of vitamins that take place during dehydration, dehydrated GLV are a concentrated natural source of micronutrients and they can be used in product formulations. Value addition of traditional products with dehydrated GLV can be advocated as a feasible food-based approach to combat micronutrient malnutrition.

Effect of maturity stages and drying methods on the retention of selected nutrients and phytochemicals in bitter melon (Momordica charantia) leaf

The purpose of this study was to investigate the nutrient and phytochemical composition of bitter melon leaves under varying maturity levels and drying techniques. Fresh, oven-dried, and freeze-dried leaves were evaluated over 3 maturity stages. In fresh leaves at various stages, crude fat, crude protein, and soluble dietary fiber contents ranged from 4.2% to 13.6%, 6.4% to 23.1%, and 0.04% to 3.50% on dry-weight basis, respectively. The contents of K, Ca, Mg, Fe, and Zn ranged from 1850.8 to 2811.8, 837.4 to 4978.2, 317.3 to 512.4, 8.4 to 16.7, and 4.1 to 5.9 mg/100 g dry-weight basis, respectively. Vitamin C, beta-carotene, and lutein contents ranged from 397.4 to 1275.1, 154.2 to 422.8, and 737.6 to 1304.6 microg/g dry-weight basis. The major flavonoids and phenolic acids were rutin, gentistic acid, and o-coumaric acid, which ranged from 7.57 to 12.75, 2.53 to 10.11, and 4.24 to 9.75 mg/g dry-weight basis, respectively. In oven-dried samples, 40.2% to 52.3% of vitamin C, 35.4% to 55.4% of beta-carotene, 25.6% to 71.6% of lutein, 26.4% to 84.0% of rutin, trace to 11.4% of gentistic acid, and 7.4% to 46.6% of o-coumaric acid were retained, while the retainment ratios of these components in freeze-dried samples were 84.7% to 99.0%, 76.4% to 99.3%, 90.4% to 96.1%, 39.8% to 99.3%, 24.1% to 68.4%, and 75.8% to 87.0%, respectively. The data showed that freeze-drying better preserves the nutrient and phytochemical quality of bitter melon leaves in comparison to oven-drying. Bitter melon leaf is a rich source of selected nutrients and phytochemicals.

Evaluation of various physico-chemical properties of Hibiscus sabdariffa and L. casei incorporated probiotic yoghurt

The present investigation was carried out to examine the effect of Hibiscus sabdariffa Calyx extract on the physico-chemical properties, sensory attributes, texture and microbial analysis of L. casei incorporated in probiotic yoghurt after manufacture and during storage. Incorporation of Hibiscus sabdariffa Calyx extract into the probiotic yoghurt resulted into decrease in coagulation time by 25 min. The pH ranged from 4.39 to 4.59, TA 0.81 to 1.14%, moisture 3.05 to 3.37 g%, syneresis 18.85 to 24.90 mL/50 g of sample, % inhibition 12.32 to 59.43, TS 21.27 to 24.90 g% and beta-galactosidase activity 1.041 to 3.277. The protein content ranged between 4.11 and 4.14 g% while the fat content ranged between 3.43 and 3.49 g%. No major changes in sensory evaluation were observed on the day of manufacture and during storage for 7 days. Sabdariffa added yoghurt showed a higher score in almost all sensory attributes. Microbial analysis showed a total plate count ranging from 1.8 x 10(4) to 1.85 x 10(7) cfu mL(-1). Yeast and mold counts were negligible in the Sabdariffa yoghurts. Thus the study concludes that incorporation of Hibiscus sabdariffa extract in yoghurt improved the total antioxidant property, organoleptic qualities and decreased the exudation of whey proteins (Syneresis). Thus, Hibiscus sabdariffa Calyces has beneficial influence on the quality of L. casei incorporated probiotic yoghurt.